Coupons for specific products

Create a coupon COUP001 worth 100%
Assign it to product PROD0001

If customer orders several products including PROD0001 and uses the coupon COUP001 the 100% discount applies to the whole order, not just to PROD0001.

Would be useful if had an option so that the 100% voucher discount applied only to PROD0001 and not to the other products.

A way round this would be to specify a specific amount (E.G. the price of PROD0001) rather than a 100% discount, but would prefer to have just a single voucher which was independent of any changes to the price of PROD0001.

As you probably know, coupons are applied to the total amount of the cart.
When you set a product in the product option of a coupon, it means: "only usable if product XX is in the cart" and not: "only usable for product XX".
Unfortunately, I don't see an easy way to change that.

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